Пример #1
0
  @Override
  public void outAConcat(AConcat node) {
    AUnExp[] unExps = (AUnExp[]) node.getUnExps().toArray(new AUnExp[0]);

    if (unExps.length == 0) {
      setOut(node, new NFA());
    } else if (unExps.length == 1) {
      setOut(node, getOut(unExps[0]));

      // free memory
      if (getOut(unExps[0]) != null) setOut(unExps[0], null);
    } else {
      NFA result = null;

      for (int i = unExps.length - 1; i >= 0; i--) {
        Object o = getOut(unExps[i]);
        NFA nfa = (o instanceof NFA) ? (NFA) o : new NFA((CharSet) o);

        if (result == null) {
          result = nfa;
        } else {
          result = nfa.concatenate(result);
        }

        // free memory
        if (getOut(unExps[i]) != null) setOut(unExps[i], null);
      }

      setOut(node, result);
    }
  }
Пример #2
0
  @Override
  public void outARegExp(ARegExp node) {
    AConcat[] concats = (AConcat[]) node.getConcats().toArray(new AConcat[0]);
    NFA result = null;

    if (concats.length > 1) {
      for (int i = concats.length - 1; i >= 0; i--) {
        Object o = getOut(concats[i]);
        NFA nfa = (o instanceof NFA) ? (NFA) o : new NFA((CharSet) o);

        if (result == null) {
          result = nfa;
        } else {
          result = nfa.alternate(result);
        }

        // free memory
        if (getOut(concats[i]) != null) setOut(concats[i], null);
      }
      setOut(node, result);
    } else if (concats.length == 1) {
      setOut(node, getOut(concats[0]));

      // free memory
      if (getOut(concats[0]) != null) setOut(concats[0], null);
    }
  }
Пример #3
0
  @Override
  public void outATokens(ATokens node) {
    ATokenDef[] tokenDefs = (ATokenDef[]) node.getTokenDefs().toArray(new ATokenDef[0]);
    NFA result = null;

    for (int i = tokenDefs.length - 1; i >= 0; i--) {
      NFA nfa = (NFA) getOut(tokenDefs[i]);
      if (nfa != null) {
        if (result == null) {
          result = nfa;
        } else {
          result = nfa.merge(result);
        }

        // free memory
        if (getOut(tokenDefs[i]) != null) setOut(tokenDefs[i], null);
      }
    }

    if (result != null) setOut(node, result);
  }
Пример #4
0
  @Override
  public void outAUnExp(AUnExp node) {
    Object o = getOut(node.getBasic());

    char c = ' ';
    if (node.getUnOp() != null) c = ((Character) getOut(node.getUnOp())).charValue();

    switch (c) {
      case '*':
        {
          NFA n = (o instanceof NFA) ? (NFA) o : new NFA((CharSet) o);
          setOut(node, n.zeroOrMore());
        }
        break;
      case '?':
        {
          NFA n = (o instanceof NFA) ? (NFA) o : new NFA((CharSet) o);
          setOut(node, n.zeroOrOne());
        }
        break;
      case '+':
        {
          NFA n = (o instanceof NFA) ? (NFA) o : new NFA((CharSet) o);
          setOut(node, n.oneOrMore());
        }
        break;
      default:
        {
          setOut(node, o);
        }
        break;
    }

    // free memory
    if (getOut(node.getBasic()) != null) setOut(node.getBasic(), null);
    if (getOut(node.getUnOp()) != null) setOut(node.getUnOp(), null);
  }
Пример #5
0
  /**
   * Generates a scanner for the specified input file.
   *
   * @param inputFile a file containing a lexical specification to generate a scanner for.
   */
  public static void generate(File inputFile) {

    Out.resetCounters();

    Timer totalTime = new Timer();
    Timer time = new Timer();

    LexScan scanner = null;
    LexParse parser = null;
    FileReader inputReader = null;

    totalTime.start();

    try {
      Out.println(ErrorMessages.READING, inputFile.toString());
      inputReader = new FileReader(inputFile);
      scanner = new LexScan(inputReader);
      scanner.setFile(inputFile);
      parser = new LexParse(scanner);
    } catch (FileNotFoundException e) {
      Out.error(ErrorMessages.CANNOT_OPEN, inputFile.toString());
      throw new GeneratorException();
    }

    try {
      NFA nfa = (NFA) parser.parse().value;

      Out.checkErrors();

      if (Options.dump) Out.dump(ErrorMessages.get(ErrorMessages.NFA_IS) + Out.NL + nfa + Out.NL);

      if (Options.dot) nfa.writeDot(Emitter.normalize("nfa.dot", null)); // $NON-NLS-1$

      Out.println(ErrorMessages.NFA_STATES, nfa.numStates);

      time.start();
      DFA dfa = nfa.getDFA();
      time.stop();
      Out.time(ErrorMessages.DFA_TOOK, time);

      dfa.checkActions(scanner, parser);

      nfa = null;

      if (Options.dump) Out.dump(ErrorMessages.get(ErrorMessages.DFA_IS) + Out.NL + dfa + Out.NL);

      if (Options.dot) dfa.writeDot(Emitter.normalize("dfa-big.dot", null)); // $NON-NLS-1$

      Out.checkErrors();

      time.start();
      dfa.minimize();
      time.stop();

      Out.time(ErrorMessages.MIN_TOOK, time);

      if (Options.dump) Out.dump(ErrorMessages.get(ErrorMessages.MIN_DFA_IS) + Out.NL + dfa);

      if (Options.dot) dfa.writeDot(Emitter.normalize("dfa-min.dot", null)); // $NON-NLS-1$

      time.start();

      Emitter e = new Emitter(inputFile, parser, dfa);
      e.emit();

      time.stop();

      Out.time(ErrorMessages.WRITE_TOOK, time);

      totalTime.stop();

      Out.time(ErrorMessages.TOTAL_TIME, totalTime);
    } catch (ScannerException e) {
      Out.error(e.file, e.message, e.line, e.column);
      throw new GeneratorException();
    } catch (MacroException e) {
      Out.error(e.getMessage());
      throw new GeneratorException();
    } catch (IOException e) {
      Out.error(ErrorMessages.IO_ERROR, e.toString());
      throw new GeneratorException();
    } catch (OutOfMemoryError e) {
      Out.error(ErrorMessages.OUT_OF_MEMORY);
      throw new GeneratorException();
    } catch (GeneratorException e) {
      throw new GeneratorException();
    } catch (Exception e) {
      e.printStackTrace();
      throw new GeneratorException();
    }
  }
Пример #6
0
 // Calculates the start state of the DFA
 private void findStart(NFA nfa) {
   DFAState dummy = new DFAState("", false, new HashSet<State>(), new HashMap<String, DFAState>());
   dummy.addState(nfa.getStart());
   start = closure(dummy);
 }